CJ750 toolbox




























Testing and replacing a defective ignition switch by Richard Cook

You will need a hex socket and ratchet, some type of pliers, I like small water pump type, or if you have it a special socket for the switch nut. Nobody ever has that sucker but the factory though, just use care with the pliers and paint. Your headlight fastener might also use another type of screw, so get what you need for that. I used a standard test light sold in any auto parts store, I carry one in my bike at all times.

Remove the bolt on the bottom of the headlight and lift it up and out to release. You can either put a rag down to protect the fender or unplug the bulb to remove it completely.

Ground the test light and put it on a hot lead to test. I always test a light before depending on it. This is something you learn the hard way. In this case I used the breaker where I bring in my power. If we have light we have power and ground, viola!

Since you can see where the lead comes to the switch from the breaker you know the main power terminal. In this case I only have my run with lights off circuit dead and frankly, I already think it’s the switch. If they give you three switches with a bike it may mean something. They also gave me three petcocks, hummmmmm. Ordinarily with a completely dead switch the first terminal you would test is the main power to see if you had juice to the switch. In this case I know I have power since the bike runs on the lights on position. So naya, naya, naya, I’m not going to bother.

I put a relay on my light circuit so if I’d been thinking I did not have to test that one either but I did out of habit. Of course it comes on with the switch since the lights work, duhhh. Your bike probably runs this wire to a very poor imitation of a European terminal connector a la BMW, Mercedes, VW, et al in the 60s. There are two of these wire blocks on my bike, the one to the left is the lights on terminal and the one to the right is the hot with engine on block. Frankly they are poorly made and should be replaced before any long trips. The screws are capable of cutting the wires and corrosion would be easy in the not very water tight headlight area.

The terminal in question is the one way behind the switch of course. This is the way life works. I’m pretty sure the wire is good because if this did not make connection I’d have no power at the hot while on terminal with any position and the bike would not have run at all. So I unplug the wire and put the switch in the run only position and as you can see no light. Well aren’t we surprised!

Now at this point a smart person would disconnect the battery as testing is over. This switch is condemned to be labeled “one bad terminal” and put on my parts shelf for desperate emergencies like earthquake or flood.

I suppose if I was smart I’d go get a universal ignition switch and install it like I did my other bike, but I have two more of these to use up and they seem to last about a season. I would replace it before I took a long trip with it, I don’t like the spade terminals much either anyway. They are nice to replace quickly, but far more likely to make you replace them quickly.

All you need to run without a switch is a piece of jumper wire and for one of these spade types with a Chang, if you hook three spade terminals together you have a plug in jumper. You could then run a toggle outside to get home or just twist a couple of wires together. An ignition switch is no biggie on one of these. My brother in law did not even know my switch broke one position and I forgot to tell him when we got back home. I’m not sure it would have helped his confidence.

You can see the fine new ignition switch in the picture, and if you have one of these you will be replacing it sometime.

Hold the switch inside the headlight while you turn the nut with your choice of high tech tool. In this case small water pump pliars.

When the nut is off drop it back in the housing like this. If you don’t remove the wires before this point you will know where they go won’t you? I have made a few trips to friend’s houses because they failed to record where the wire went before removing a component. If you just fold it back like this you can locate a mark to be sure you have the order correct, in this case both switches have a 24 marked on them in the same position.

The old style fuse which might be used for a main fuse on your bike, and the generator light are on the plastic piece under the switch. Handle them carefully.

Note that I’ve placed the other switch next to the old one while I transfer the wires.

Now I test the switch before I reinstall it. Then disconnect the battery again and fit the switch using a drop of blue Loctite. Tighten carefully with your high tech tool.

Now I like to test the switch again before installing the headlight.

Then do a final headlight installation as in the last picture and you are ready for a road test. If you disconnected the battery clean the connections and check the water.

No actual road test for me though as since if it had not been raining I would have just ridden the bike until it rained.